Conventionally, in a multi function peripheral (MFP) in which an electrophographic method is employed in a printer unit, a large amount of electric power is necessary for image forming. In particular, for a fixing unit, an image forming unit, a circuit for processing image data and the like, electric power consumption is large. Meanwhile, due to increase in energy conservation consciousness, strengthening of regulations and the like in recent years, the necessity to perform electric power control meticulously is increasing. For example, in Japanese Patent Laid-Open No. 2010-161848, it is recited that when a rated value of a breaker is approached, a user is notified, and an electric power of a device is turned off. Furthermore, a technique is considered in which, in a case where a power demand amount increases and a power supply capability is pressed, by automatically causing an electric power supply amount to change as well as turning off an electric power of a device that is consuming electric power, an electric power consumption amount is reduced and an electric power peak is restrained.
However, in the case of such a situation, a problem is in the point that a user using the device cannot distinguish whether the power of the device was turned off because the electric power supply amount was pressed or whether the power was simply turned off. Furthermore, regardless of the fact that the power of the device was turned off because the electric power supply amount was pressed, there is a possibility of an electric power consumption amount increasing due to the user turning on the power of the device, and a situation occurring in which an electric power supply amount is exceeded.